This invention relates to the novel use of engineered composite systems that are formulated and applied in building structures using common and special construction materials in unique and distinct combinations. The materials and processes produce a very cost effective structure with superior Electromagnetic Pulse (EMP) protective attributes with shorter construction time than structures that are currently being used for EMP protection structures and systems. The EMP Protective composite enclosure panel systems and materials in this application have unique features that allow for, if required, exceptional corrective and maintenance work which can be easily located and performed to allow for long-term Intentional Electro Magnetic Interference (IEMI) and EMP shielding, absorption and conductivity protection requirements of the system(s) for many decades, if not longer, to come.
With the increase in awareness and interest in the United States of America's national security as detailed in the President Trump's Executive Order on Coordinating National Resilience to Electromagnetic Pulses dated Mar. 26, 2019 and with the two Electromagnetic Defense Task Force reports from the USAF LeMay Center for Doctrine Development and Education, report 1.0 issued in 2108, and another report in 2019 and with several congressional hearings' testimony on the devastating consequences of a man-made Electromagnetic Pulse (EMP) or a naturally occurring Geomagnetic Disturbances (GMD) event occurring in the United States, there has recently been a keen interest from governmental departments, agencies, public utilities and investor owned utilities (IOU) on how best to provide high quality and cost effective EMP protective structures and systems.
U.S. Pat. No. 9,790,703, “Methods of Utilizing Coal Combustion Residuals and Structures Constructed using such Coal Combustion Residuals”, discloses structures suitable for EMP protected structures. There is a need for not only the Coal Combustion Residuals EMP protective structures under U.S. Pat. No. 9,790,703, but there is also the need for other types of EMP protective structures and systems.
The majority of recently built EMP protective structures are presently constructed by one of two methods. The most common currently used method is a system disclosed in U.S. Pat. No. 8,968,461 licensed to Omni-Threat Structures (OTS) by the University of Nebraska which is centered around an electrically-conductive concrete mix design, also sponsored by the US Government.
Additionally, OTS has licensed U.S. Pat. No. 9,681,592 from the University of Nebraska. This patent discloses a magnetic conductive material that is embedded in the electrically-conductive concrete. This technology was also sponsored by the US Government.
A second type of EMP protection system is also currently an option in the marketplace. This method includes the use of a composite panel system made of light gauge metal with a high-density wood core which is mechanically fastened or connected with welded light-gauge joints with a ½ inch thick cement backer board that is used for protection of the components during the welding process. A mechanically fastened option available from Braden Shielding Systems was used for Dominion Energy's System Operation Center (SOC) which opened in August 2017 and is hardened against natural and man-made EMP threats. “The center includes a MIL-SPEC EMP space for critical operations and employs the latest technologies and practices in physical and cyber security, telecommunications, redundancy and efficiency,” as stated by David W. Roop, P.E. with Dominion Energy in testimony before the Committee on Homeland Security and Governmental Affairs, Feb. 27, 2019.
In the Braden Shielding approach, a non-loadbearing EMP protective system is constructed inside a traditional building, which is a very different method than the load bearing structure approach found in the University of Nebraska patent that is used by OTS. The shielding that Braden Shielding Systems, as used in the Dominion Energy project is comparable to other shielding systems in the marketplace, such as ETS-Lindgren which utilized a composite panel system to construct a HEMP shielded facility in Houston, Tex. for Centerpoint Energy.
ETS Lindgren provides a composite system which is constructed with Laminated Veneer Lumber (LVL) and galvanized steel which is mechanically fastened. In addition, brass wool and copper tape is used to cover the mechanically-fastened seams.
At least one other vendor also provides composite panel shielding systems—Universal Shielding.
Several other older patents also disclose conductive cement-based compositions, e.g., U.S. Pat. Nos. 5,447,564, 3,166,518, and Canadian Patent 2404513.
Regarding the Braden Shielding and ETS-Lindgren approaches, the use of non-durable brass wool and copper tape as integral shielding elements and their cost affordability impediments along with their long-term integrity concerns for large scale projects using light-gauged metal and wood composite panels, the (MIL-HDBK-1195) cautions against the use of mechanically-fastened panel shielding systems, largely due to the expense of maintenance and questionable durability. These designs are not load-bearing structural panels that become part of the structural components of the structure. Quality control, excessive cost to construct and scheduling challenges with the multiple meshes embedded in conductive concrete as outlined in the University of Nebraska patents present other considerations.
Man-made EMP created by the detonation of a nuclear weapon above the earth surface will create electromagnetic forces that have different frequency ranges and different rates of onset time, duration and intensity which cause the electrical and magnetic forces to arrive to a definite point in space at different times and with different types of energy and different field strengths of energy.
These different Electrical and Magnetic energy levels are referred to in the scientific community as E1, E2, and E3. To protect against the negative forces of an EMP, engineers knowledgeable in EMP protection design features to provide protection of vulnerable components, items, and/or equipment by either absorption, shielding or reflection, or a combination of all three methods to protect components from damage by an EMP event. A building must be protected against an EMP event on all sides of the structure, including from the underside of the structure, as well as the roof level, in addition to all vertical or slanted sides of the structure.
There are two known composite steel and concrete systems that are not designed for and do not provide EMP protection. These composite steel/concrete systems are designed for an entirely different purpose, which is to speed the construction schedule of mid-rise and high-rise buildings and are not designed to provide for, nor do they provide, EMP protection. One system is referred to as AISC “Speed Core” and the other system is referred to as REDICOR and is manufactured by Vulcraft, a unit of NuCor Steel.
Panels in accordance with the disclosure of this application can be fabricated using what is a known construction method called “tilt-up” concrete wall panel construction, practiced by, for example, Dayton Superior. Tilt-up concrete wall panel construction methods include a casting bed, which is commonly the slab on grade of the building. Once a casting bed is constructed, the perimeter of the panels are typically formed with temporary wood or metal forms to hold the concrete in place after the reinforcing steel bars or welded wire fabric is installed. The reinforcements are placed in the forms; the concrete is poured, finished and cured. After the concrete reaches the required strength, the panels will be lifted (tilted-up) from the slab with a crane and then set into place and braced until other parts of the structure are assembled or constructed which will permanently secure the complete building structure and join the tilt-up concrete panels together.